Zone 2 Cardio Explained

Zone 2 cardio is all of the rage right now.

Even the biggest meatheads who were previously terrified of cardio are getting on board.

Looking at google trends, there seems to be over double the search volume compared to one year ago (at the time of this writing).

As with an increased interest, I have similarly received an increase in questions on the topic.

So, my aim with this article is to explain the following:

• What is zone 2 cardio?

• What makes zone 2 so helpful?

• How should you do your zone 2 cardio?

• How much zone 2 cardio should you be doing?

As always, if you have questions you feel went unanswered throughout this article, please feel free to email me at info@FitnessSimplified.org or comment below. I’m always happy to help.

What is ‘zone 2’ cardio?

‘Zone 2’ refers to a specific heart rate zone in accordance with the 5 zone model of endurance training.

• Zone 1 = 50-60% Max Heart Rate

• Zone 2 = 60-70% Max Heart Rate

• Zone 3 = 70-80% Max Heart Rate

• Zone 4 = 80-90% Max Heart Rate

• Zone 5 = 90-100% Max Heart Rate

  • Max Heart Rate = 220 - your age (this is an estimation & varies person to person; a max heart rate test is needed to definitively find out your max heart rate)

What makes zone 2 cardio so helpful?

Zone 2 cardio is often referred to as the “aerobic zone.”

This is the point where you are moving intensely enough to promote significant adaptations to your cardiovascular/aerobic system, but not intense enough to the point where you accrue any significant muscle damage.

This makes zone 2 “hyper-recoverable,” in a sense.

Assuming you perform the same amount of time, you’d get similar adaptations from training in zone 3 or low zone 4.

The problem there, though, is that your body needs much more time to recover from those zones.

Therefore, the overall amount of volume (in terms of time) you can perform is inhibited in those zones, and they may interfere with strength training to a higher degree.

In other words, zone 2 cardio allows you to perform significantly higher volumes with less recovery time; also making it easier to combine with strength training.

This is beneficial because improvements in endurance are in large-part driven by the volume of cardio you do.

So, by enabling you to do more cardio overall, zone 2 is therefore beneficial.

How should you do zone 2?

What sort of exercises should you be doing for zone 2?

When it comes to specifically targeting this heart rate zone: some exercise choices are good, others might not be.

So, what you should aim for is this:

• no (or, low) impact

• no eccentric (no lowering of a weight)

• cyclical (involves repetitive actions

What are some examples of this?

• bicycle (stationary or on road)

• AirDyne

• SkiErg

• Concept 2 Rower

Running, in my opinion, can be a bit of a grey area when it comes to zone 2 training specifically.

Truth is, you’ve got to be a pretty advanced runner in order to consistently run at a zone 2 heart rate.

Most people will spike to high zone 3 or zone 4, even at a slow pace, while running.

As a result, it isn’t my favorite modality for most people- starting out at least.

If you want to try to do some running at or around a zone 2 intensity, here are how I recommend you go about it:

• Use jog/walk intervals

  • There are three ways you can go about doing this:

    • Go by heart rate. Jog until your heart rate hits ~70-75% max heart rate. Then, walk until your heart rate comes down to ~55-60% max heart rate. Have a total work time in mind, and repeat this until you’ve completed the time you aimed to complete.

    • Time intervals. Ideally, you want at least a 2:1 work:walk ratio. This tends to work best for people who are beginners to running.

    • Distance intervals. This works best for people who have a good understand of their abilities on specific distances. With these, I usually keep the walk to 0.25 miles and modify the run interval distance to the person I’m working with.

How much zone 2 cardio should you do?

There’s no possible way for me to give you a straight answer to this question.

It depends and varies largely based on why you’re doing the zone 2 work in the first place.

If you’re brand new to this type of exercise, my recommendation is usually the same:

• 2x per week

• 20 minutes

From here, I’d recommend adding ~10 minutes per week in any form you prefer. That can be two 25-minute sessions, or it can be a 30-minute session and a 20-minute session. I would only recommend adding it in the form of another session if that session would be at least 20 minutes (which would happen in your second week of progression).

If your goal with doing zone 2 work is to improve health & longevity:

then meeting the ACSM’s activity guidelines with zone 2 work is the minimum you should aim for.

They recommend at least 150 minutes per week (2.5 hours per week) of exercise at this intensity.

If your goal with doing zone 2 work is to improve endurance and cardiovascular/aerobic performance:

then you’ll want to aim for a minimum of 4 hours per week.

Conclusion

My goal here was to provide you with a ~5-minute read that would leave you feeling supremely competent in what zone 2 cardio is and how to do it. To me, this stuff is important. It clearly is to you too to a degree, otherwise I don’t think you’d be here reading this article right now.

As usual, if you feel you still have questions that were left unanswered, you are welcome to email me at info@FitnessSimplified.org.